Are DNA tests reliable enough to verify ancestry from Africa? How many generations would appear in such results, since if we go back enough we'll find that human race generated in the African continent?
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There has been a growing interest in the historical roots of African Americans and other communities of recent African ancestry, and genetics can play an important role in the study of that ancestry. However, much of the work to date has focused either on the extent of the African contribution to the American gene pool (Chakraborty et al. 1992; Parra et al. 1998, 2001; Mesa et al. 2000; Sans 2000) or on particular mtDNA lineages carried to the Americas through the Atlantic slave trade (Alves-Silva et al. 2000; Bandelt et al. 2001; Pereira et al. 2001; Salas et al. 2002). Despite widespread public interest and the rapidly growing involvement of private companies in genetic ancestry testing, the only published attempt to date to assign African geographical ancestry to African American lineages by use of genetic data has been by Salas et al. (2004). This latter work suggested a majority contribution of West Africa to the mtDNA pool of North and Central Americans of recent African descent, with a slightly smaller component from west-central Africa, whereas African Americans from South America (Brazil) reversed the picture, with a larger west-central African component. No significant component was detected from other regions, including Mozambique, despite the historical evidence of the movement of ∼1 million slaves from that region (Thomas 1998). Eurasian mtDNAs of recent African ancestry were found to be made up mainly of west-central and North African components, with a larger East African component in the Near East.
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